大菱鲆(Scophthalmus maximus)幼鱼生长性状的遗传力及其相关性分析

以4种不同地理群体大菱鲆为亲本，采用巢式设计方法和人工采卵授精技术，按照1雄配2雌的原则，构建了28个父系半同胞家系和56个母系全同胞家系，分别测定了每个母系生长到6月龄的全同胞个体60个后代的体长、全长、体高、体重，应用数量遗传学原理，利用全同胞资料，采用方差、协方差分析的方法，研究了大菱鲆6月龄生长性状的遗传力及性状间的遗传相关和表型相关。对性状遗传力研究结果表明，雌性遗传方差组分均大于雄性遗传方差组分，雌性遗传方差组分存在显著的母性效应。基于父系半同胞组内相关法估计的遗传力是大菱鲆体长、全长、体高、体重遗传力的无偏估计值，估计的遗传力准确可靠，估计值分别为0．282、0．251、0．283、0．450，为中高等遗传力，显示对大菱鲆生长性状进行选择育种具有很大的潜力。对性状间相关性分析结果表明，依据父系半同胞遗传协方差组分和表型协方差分别估计体长．全长、体长一体高、体长．体重、全长。体高、全长一体重、体高一体重间的遗传相关和表型相关，遗传相关在0．888-0．985，表型相关在0．864—0．957，各性状间遗传相关和表型相关经t检验均达到极显著水平（P〈0．01）。

THE GROWTH TRAITS AND THEIR HERITABILITY OF YOUNG TURBOT (SCOPHTHALMUS MAXIMUS L.)

Parents Scophthalmus maximus L. from four different populations were studied in a nest design with an artificial insemination. Twenty eight half-sib families and 56 full-sib families were used, in which each male mated 2 females. Sixty 6-month-old young animals were measured in each full-sib family for body length (cm), total length (cm), body depth (cm) and body weight (g). According to quantitative genetics theory, the heritability of each growth trait, and the genetic and phenotypic correlation among the traits were statistically studied. The results show that the maternal component estimates are significantly larger than those of paternal ones for each growth trait, suggesting that the large non-additive genetic effects could not be differentiated from the available data. The heritability estimates in the narrow sense from intra group correlation of paternal half-sib were precise and unbiased at 0.282, 0.251, 0.283, and 0.450 for the body length, total length, body depth, and body weight, respectively. The estimates of genetic and phenotypic correlation coefficients are 0.888-0.985 and 0.864-0.957, respectively, in very significant difference (P < 0.01) among the four growth traits by t-test.